We report the development of inkjet-printed organic thin-film transistors (OTFTs), inverters and logic circuits on PET substrate. The mobility of 1 cm²/Vs and 0.1 cm²/Vs achieved on p-type and n-type printed OTFTs with an operation voltage of 15 V. The printed uniform and thin dielectric layer achieved by introducing coffee ring effect on printing process. A gain value of 24 obtained from the printed CMOS inverter and the device exhibits an excellent air-stability without encapsulation. Our results demonstrated the potential of the developed printed transistors for flexible electronics in the near future.